He had played in the Eastern League before coming to the majors, and went into real estate afterwards.

Minor leaguer Gus Moran stated in Sporting Life in 1904 that he was responsible for Keeler getting into pro ball. John Rainey broke his leg in 1892 while playing for Binghamton, and as a possible replacement Moran suggested the manager have someone take a look at young Keeler, playing ball at the time for the amateur Acmes of New York. Keeler was signed and hit .373 at age 20 for Binghamton; second best on the team was Quiet Joe Knight, a 32-year-old veteran who had hit .312 in the majors in 1890 and hit .358 for Binghamton in 1892.

". . . he had a trick of hitting a high hopper to an infielder. The ball would bounce so high that he was across the bag before he could be stopped." - Honus Wagner

"I was just thinking of those suckers, the club owners, paying me for playing ball. Why, I would pay my way into their ballparks if that was the only way I had to get into a game." - Willie Keeler

"I hit 'em where they ain't." - Willie Keeler

"Speaking of sun-fields (fields where outfielders face into the sun), such as the one at Cub Park, it is the belief of Addie Joss that such fields ruin the batsmen who have to play in them, and that this has killed off the hitting of Keeler and other stars." - Sporting Life, Jan. 16, 1909